A study is to be made of the electrochemistry of alkylcobalamins and alkylcobinamides using polarography, cyclic voltammetry, and potential step chronoamperometry. By eliminating adsorption effects it should be possible to determine standard reduction potentials and decomposition rates for alkyl cleavage for a series of these compounds. The catalytic hydrogen wave phenomena will also be studied in order to measure kinetic parameters and develop an ultra-trace electroanalytical technique for vitamin B12 derivatives. An attempt will be made to probe cobalt-axial ligand bonding using resonance Raman spectroscopy. The laser excitation frequency will be varied in an attempt to excite charge-transfer bands or d-d metal transitions. The techniques of gel filtration and e.s.r. will be used to study complexes of vitamin B12r with thiols as well as other ligands. Kinetics of the reactions of vitamin B12r, prepared electrochemically, with thiols, other ligands, and oxidizing agents will be studied using the techniques of optical spectroscopy, thin layer spectroelectrochemistry, and various forms of voltammetry.